Ethylene oxide/propylene block copolymers have been utilized in detergent as surfactants. A variety of such block copolymers is commercially available from BASF Wyandotte Corporation of Wyandotte, Mich. under the tradename Pluronic.RTM. surfactants, Pluronic.RTM. R surfactants, Tetronic.RTM. surfactants and Tetronic.RTM. R surfactants.
Polycarboxylates have been utilized as detergency builders. For example, U.S. Pat. No. 3,128,287, U.S. Pat. No. 3,635,830, U.S. Pat. No. 4,144,226, U.S. Pat. No. 4,146,495 and European patent application 192,441, published Aug. 27, 1986, disclose certain ether carboxylates as detergency builders. U.S. Pat. No. 3,933,673 describes the use of partial alkali metal salts of homo or copolymers of unsaturated aliphatic mono-or polycarboxylic acids as builders.
U.S. Pat. No. 4,657,693 discloses a spray dried detergent composition comprising a nonsoap anionic detergent surfactant, an alkali metal tripolyphosphate detergent builder and certain mixtures of a polyethylene glycol and a polyacrylate. It is stated that the polyacrylate/polyethylene glycol mixtures provide a boost to dispersion rates in cold water and improvement in physical properties.
U.S. Pat. No. 4,490,271 discloses a granular detergent composition comprising an organic surfactant, a nonphosphorous detergent builder and a certain mixtures of a polyethylene glycol and polyacrylate. It is stated that such polyacrylate/polyethylene glycol mixtures provide a boost to the removal of clay soils.
It has now been discovered that detergent compositions comprising a nonphosphorous detergent builder that contain mixtures of certain ethylene oxide/propylene oxide block copolymers and certain polycarboxylates provide a surprising boost to the removal of clay soils.